Single-cell profiling reveals differences between human classical adenocarcinoma and mucinous adenocarcinoma.

Colorectal cancer is a highly heterogeneous disease. Most colorectal cancers are classical adenocarcinoma, and mucinous adenocarcinoma is a unique histological subtype that is known to respond poorly to chemoradiotherapy. The difference in prognosis between mucinous adenocarcinoma and classical adenocarcinoma is controversial. Here, to gain insight into the differences between classical adenocarcinoma and mucinous adenocarcinoma, we analyse 7 surgical tumour samples from 4 classical adenocarcinoma and 3 mucinous adenocarcinoma patients by single-cell RNA sequencing. Our results indicate that mucinous adenocarcinoma cancer cells have goblet cell-like properties, and express high levels of goblet cell markers (REG4, SPINK4, FCGBP and MUC2) compared to classical adenocarcinoma cancer cells. TFF3 is essential for the transcriptional regulation of these molecules, and may cooperate with RPS4X to eventually lead to the mucinous adenocarcinoma mucus phenotype. The observed molecular characteristics may be critical in the specific biological behavior of mucinous adenocarcinoma.

Organoid in colorectal cancer: progress and challenges.

Patient-derived tumor organoids (PDOs) currently represent important modeling tools in pre-clinical investigation of malignancies. Organoid cultures conserve the genetic and phenotypic characteristics of the original tumor and maintain its heterogeneity, allowing their application in many research fields. PDOs derived from colorectal cancer (CRC) have been used for genetic modeling to investigate the function of driver genes. Some researchers have been exploring the value of CRC PDOs in chemotherapy, targeted therapy, and radiotherapy response prediction. The successful generation of PDOs derived from CRC could deepen our understanding of CRC biology and provide novel tools for cancer modeling, for realizing precision medicine by assessing specimens from individual patients ex vivo. The present review discusses recently reported advances in CRC PDOs and the challenges they face as pre-clinical models in CRC research.

Prognostic value of CD45RO(+) tumor-infiltrating lymphocytes for locally advanced rectal cancer following 30 Gy/10f neoadjuvant radiotherapy.

AIM: This study aims to evaluate the prognostic value of CD45RO(+) tumor-infiltrating lymphocytes (TILs) in locally advanced rectal cancer treated with 30 Gy/10 fraction (10 f) neoadjuvant radiotherapy. METHODS: This retrospective study involved 185 patients with locally advanced rectal cancer who underwent 30 Gy/10 f nRT (biologic equivalent dose, 30 Gy) followed by total mesorectal excision (TME) between August 2003 and October 2009. The density of CD45RO(+) TILs was assessed by immunohistochemistry using an image-analysis system and tissue microarray and was evaluated for its association with histopathologic features along with disease-free survival (DFS). RESULTS: Following neoadjuvant radiotherapy, the median density of CD45RO(+) TILs is 654/mm(2). High density of CD45RO(+) TILs was significantly associated with increased T and N downstaging effect (p = 0.006; p = 0.014), lesser-advanced T stage (p = 0.003) and TNM stage (p = 0.022). Prolonged DFS (89.0 vs. 68.1%) was also observed in CD45RO(+Hi) cases. On multivariate regression model, CD45RO(+) TILs (p = 0.026; odds ratio (OR), 0.436 (95% confidence interval (CI), 0.209-0.907)), tumor differentiation (p = 0.057; OR, 1.878 (95% CI, 0.982-3.593)), ypT stage (p = 0.066; OR, 2.383 (95% CI, 0.943-6.025)), and ypN stage (p = 0.009; OR, 2.612 (95% CI, 1.266-5.388)) were independent factors for DFS. CONCLUSION: The density of CD45RO(+) TILs cannot only predict tumor downstaging and ypTNM stage for rectal cancer following 30 Gy/10 f nRT but also promisingly predict long-term outcomes. These findings may be used to stratify patients and make alternative strategy of adjuvant treatment.

Downregulation of miR-193a-5p correlates with lymph node metastasis and poor prognosis in colorectal cancer.

AIM: To investigate the correlation of miR-193a-5p with lymph node metastasis and postoperative survival of colorectal cancer (CRC) patients. METHODS: A total of 304 formalin-fixed, paraffin-embedded specimens (69 paired cancer and normal tissues, 55 primary tumors of stage III CRC and matched lymph nodes, and 56 primary tumors of stage II CRC) were included in this study. The relative expression levels of miR-193a-5p in the normal mucosa, primary cancer, and metastatic lymph node lesions were measured by quantitative real-time reverse transcriptase polymerase chain reaction. We evaluated the association of its expression with colorectal cancer lymph node metastasis, clinicopathological factors, and patient survival. RESULTS: The relative expression level of miR-193a-5p was significantly lower in CRC tissues than in the normal mucosa (P = 0.0060). The expression levels of miR-193a-5p were lower in primary CRC tissues with lymph node metastases than in those without metastases (P = 0.0006), and decreased expression of miR-193a-5p correlated with advanced lymph node metastatic stage (P = 0.0007). Kaplan-Meier analysis showed that patients with low miR-193a-5p expression had decreased disease-free survival (DFS) (P = 0.0026) and poor overall survival (OS) (P = 0.0003). Interestingly, for the group of patients with lymph node metastases, miR-193a-5p expression was also related to survival. Patients with low miR-193a-5p expression had decreased DFS (P = 0.0262) and poor OS (P = 0.0230). Moreover, multivariate analysis indicated that downregulation of miR-193a-5p was an independent predictor of poor OS. CONCLUSION: Downregulation of miR-193a-5p correlates with lymph node metastasis and poor survival of CRC. miR-193a-5p may be a useful biomarker for CRC diagnosis, metastasis and prognosis prediction.

PBX3 promotes migration and invasion of colorectal cancer cells via activation of MAPK/ERK signaling pathway.

AIM: To investigate the role of pre-B-cell leukemia homeobox (PBX)3 in migration and invasion of colorectal cancer (CRC) cells. METHODS: We detected PBX3 expression in five cell lines and surgical specimens from 111 patients with CRC using real-time reverse transcription-polymerase chain reaction. We forced expression of PBX3 in low metastatic HT-29 and SW480 cells and knocked down expression of PBX3 in highly metastatic LOVO and HCT-8 cells. Wound healing and Boyden chamber assays were used to detect cell migration and invasion after altered expression of PBX3. Western blot was performed to detect the change of signaling molecule ERK1/2 following PBX3 overexpression. RESULTS: High level of PBX3 expression was correlated with the invasive potential of CRC cells, and significantly associated with lymph node invasion (P = 0.02), distant metastasis (P = 0.04), advanced TNM stage (P = 0.03) and poor overall survival of patients (P < 0.05). Ectopic expression of PBX3 in low metastatic cells was shown to promote migration and invasion, while inhibited PBX3 expression in highly metastatic cells suppressed migration and invasion. Furthermore, upregulation of phosphorylated extracellular signal-regulated kinase (ERK)1/2 was found to be one of the targeted molecules responsible for PBX3-induced CRC cell migration and invasion. CONCLUSION: PBX3 induces invasion and metastasis of CRC cells partially through activation of the MAPK/ERK signaling pathway.

Let-7c functions as a metastasis suppressor by targeting MMP11 and PBX3 in colorectal cancer.

Accumulating evidence shows that microRNAs, functioning as either oncogenes or tumour suppressors by negatively regulating downstream target genes that are actively involved in tumour initiation and progression, may be promising biomarkers and therapy targets. Data mining through a microRNA chip database indicated that let-7c may be associated with tumour metastasis. Here, we confirmed that down-regulation of let-7c in primary cancer tissues was significantly associated with metastases, advanced TNM stages and poor survival of colorectal cancer patients. Moreover, ectopic expression of let-7c in a highly metastatic Lovo cell line remarkably suppressed cell migration and invasion in vitro by the down-regulation of K-RAS, MMP11 and PBX3, as well as tumour growth and metastases in vivo, whereas inhibition of let-7c in low-metastatic HT29 cells increased cell motility and invasion by the enhanced gene expression of K-RAS, MMP11 and PBX3. Interestingly, the luciferase reporters' activities with the 3'-UTRs of K-RAS, MMP11 and PBX3 were inhibited significantly by let-7c. Importantly, rescue experiments involving the over-expression of these genes without their 3'-UTRs completely reversed the effects of let-7c on tumour metastasis, both in vitro and in vivo. Finally, the levels of let-7c were inversely correlated with those of MMP11 and PBX3, but not with those of K-RAS. Taken together, these results demonstrate that let-7c, apart from its tumour growth suppression role, also functions as a tumour metastasis suppressor in colorectal cancer by directly destabilizing the mRNAs of MMP11 and PBX3 at least.

ß-Escin sodium inhibits inducible nitric oxide synthase expression via downregulation of the JAK/STAT pathway in A549 cells.

ß-escin, a triterpene saponin, is one of the major active compounds extracted from horse chestnut (Aesculus hippocastanum) seed. Previous work has found that ß-escin sodium has antiinflammatory and antitumor effects. In the present study, we investigated its effect on cell proliferation and inducible nitric-oxide synthase (iNOS) expression in human lung carcinoma A549 cells. ß-escin sodium (5-40 µg/mL) inhibited cytokine mixture (CM)-induced nitric oxide (NO) production in A549 cells by reducing the expression of iNOS. ß-escin sodium suppressed phosphorylation and nuclear translocation of STAT1 (Tyr701) and STAT3 (Tyr705) induced by CM but did not affect the activation of c-Jun and NF-κB. ß-escin sodium inhibited the activation of protein tyrosine kinase JAK2. Pervanadate treatment reversed the ß-escin sodium-induced downregulation of STAT3 and STAT1. ß-escin sodium treatment enhanced an activating phosphorylation of the phosphatase SHP2. Small interfering RNA-mediated knockdown of SHP2 inhibited ß-escin sodium-induced phospho-STAT dephosphorylation. Moreover ß-escin sodium reduced the activation of p38 MAPK. Finally, ß-escin sodium inhibited the proliferation of A549 cells, did not change the cell membrane's permeability, nuclear morphology and size and the mitochondria's transmembrane potential of A549 cells. Taken together, these results demonstrate that ß-escin sodium could downregulate iNOS expression through inhibiting JAK/STAT signaling and p38 MAPK activation in A549 cells. ß-escin sodium has a marked antiproliferative effect on A549 cells at least in part by inhibiting the JAK/STAT signaling pathway, but not by a cytotoxic effect. ß-escin sodium would be useful as a chemopreventive agent or a therapeutic against inflammatory-associated tumor. © 2011 Wiley Periodicals, Inc.

Anti-tumor effect of Liqi, a traditional Chinese medicine prescription, in tumor bearing mice.

BACKGROUND: Liqi, an herbal preparation used in traditional Chinese medicine, has been used to treat cancer in China for centuries. We investigated the anti-tumor effects of liqi and their mechanisms in mice that had been xenografted with tumors. METHODS: Sarcoma 180 tumor, Lewis lung carcinoma, and SGC-7901 cells were implanted in BALB/c mice, C57BL/6 mice, and BALB/c nude mice, respectively. Liqi was administered to subgroups of these mice. The tumor weight and size were measured. Cell cycle analysis and T lymphocyte subsets were determined by flow cytometry. The activity of NK cells and TNF was tested using cytotoxicity assay on YAC-1 cells and L929 cells, respectively, and the activity of IL-2 was tested with an IL-2-dependent CTLL-2 cell proliferation assay. Platelet aggregation was monitored by measuring electric impedance, and the levels of thromboxane A2 (TXA2) and prostacyclin (PGI2) in blood were measured by 125I-TXB2 and 125I-Keto-PGF1alpha radioimmunoassay. RESULTS: The results showed that liqi inhibited tumor growth in tumor-implanted mice and arrested the cell proliferation in the G0/G1 phase and reduced the portion of cells in S and G2/M phase for SGC-7901 cells. Liqi increased the activity of NK cells and TNF-alpha, stimulated IL-2 production and activity, and regulated T lymphocyte subpopulations. Liqi inhibited the Lewis lung carcinoma metastasis by inhibiting platelet aggregation and normalizing the balance between TXA2 and PGI2. CONCLUSION: All these findings demonstrated that liqi has an anti-tumor effect in vivo. The mechanism may be related to immune regulation and anticoagulation effects.

Effect of Hydroxysafflor yellow A on human umbilical vein endothelial cells under hypoxia.

Hydroxysafflor yellow A (HSYA), is a component of the flower, Carthamus tinctorius L. In this study, we investigated its effect on Human Umbilical Vein Endothelial Cells (HUVECs) under hypoxia. We evaluated cell viability using the MTT kit. The cell cycle distribution was analyzed by PI staining flow cytometric analysis. PI AnnexinV-FITC detection and the TUNEL assay were performed to evaluate the apoptosis rate. Nitric oxide (NO) generation in cell supernatant was measured by the Griess assay. RT-PCR, Western blot and Immunocytochemistry analysis were used to evaluate the changes of Bcl-2, Bax, p53 and eNOS. Our data showed that HSYA inhibited cell apoptosis and cell cycle G1 arrest induced by hypoxia. HSYA treatment increased the Bcl-2/Bax ratio of protein and mRNA, reduced p53 protein expression in cell nucleus. In addition, HSYA enhanced the NO content of cell supernatant under hypoxia, accompanied with upregulating eNOS mRNA expression and protein level. Taken together, these results demonstrate that HSYA could protect HUVECs from hypoxia induced injuries by inhibiting cell apoptosis and cell cycle arrest. These findings have partly revealed the molecular mechanism of HSYA on treating of ischemic heart disease. We expected our experiments might provide some clues for further research.

Establishment of a cell-based assay to screen regulators of the hypoxia-inducible factor-1-dependent vascular endothelial growth factor promoter.

In this study, we established a drug screening system based on transcriptional regulation of vascular endothelial growth factor (VEGF) under hypoxia-inducible factor-1alpha control. We cloned the neomycin-resistance gene into the plasmid GL (pGL)3-promoter vector to generate the pGL3-promoter-neo vector. The 3 copies of the 47-bp fragment that contained the hypoxia response element of VEGF were synthesized and inserted in front of the minimal promoter of the pGL3-promoter-neo vector to generate p3HRE-luc-neo. The recombinant reporter gene vectors were transfected into EAhy926 cells, and stable cell lines were obtained. The positive cell line was selected for its ability to express luciferase in response to hypoxia. We demonstrated that CoCl(2) significantly enhances luciferase activity in a concentration-dependent fashion. We then optimized the cell density and incubation time under hypoxia which were used to screen. The assay exhibited a low background and was an ideal model for high-throughput screening for human VEGF regulators.

Hydroxysafflor yellow A enhances survival of vascular endothelial cells under hypoxia via upregulation of the HIF-1 alpha-VEGF pathway and regulation of Bcl-2/Bax.

Hydroxysafflor yellow A (HSYA) is a component of the flower Carthamus tinctorius L. The present investigation determines whether HSYA can modify the effects of hypoxia on vascular endothelial cells (EC) and its mechanisms. Human EC line (EAhy926) viability was determined using the MTT assay. EC cycle phase distribution was done with PI staining and flow cytometric analysis, and EC apoptosis was done by AnnexinV-FITC detection and the TUNEL assay. The protein levels of VEGF, Bcl-2, Bax, and HIF-1 alpha were determined by ELISA or Western blot analysis, and the mRNA expression of these genes by RT-PCR analysis. HIF-1 alpha transcriptional activity was measured using a reporter gene assay. HSYA improved cell viability under hypoxia in a concentration-dependent manner by attenuating its cycle arrest and inhibiting its apoptosis. HSYA upregulated the bcl-2/bax ratio, which is downregulated under hypoxia, increased VEGF protein concentration and VEGF mRNA expression and enhanced HIF-1 alpha protein accumulation and its transcriptional activity. In conclusion, HSAY could enhance the survival of ECs under hypoxia, which may be correlated with its effect of upregulating the bcl-2/bax ratio and promoting HIF-1 alpha protein accumulation, which increases VEGF. These findings provide evidence for the mechanisms by which HSYA maintains EC survival under hypoxia.